Crown Ether-Derived Chiral BINOL: Enantioselective Michael Addition of Alkenyl Boronic Acids to α,β-Unsaturated Ketones

Jia-Ju Tao; Jia-Dong Tang; Tao Hong; Jia-Wen Ye; Jia-Yu Chen; Chunsong Xie; Zibin Zhang; Shijun Li

doi:10.1021/acsomega.1c05875

Crown Ether-Derived Chiral BINOL: Enantioselective Michael Addition of Alkenyl Boronic Acids to α,β-Unsaturated Ketones

ACS Omega. 2021 Dec 10;6(50):35093-35103. doi: 10.1021/acsomega.1c05875. eCollection 2021 Dec 21.

Authors

Jia-Ju Tao¹, Jia-Dong Tang¹, Tao Hong¹, Jia-Wen Ye¹, Jia-Yu Chen¹, Chunsong Xie¹, Zibin Zhang¹, Shijun Li¹

Affiliation

¹ College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, P. R. China.

Abstract

A new class of aza-crown ether-derived chiral BINOL catalysts were designed, synthesized, and applied in the asymmetric Michael addition of alkenylboronic acids to α,β-unsaturated ketones. It was found that introducing aza-crown ethers to the BINOL catalyst could achieve apparently higher enantioselectivity than a similar BINOL catalyst without aza-crown ethers did, although the host-guest complexation of alkali ions by the aza-crown ethers could not further improve the catalysis effectiveness. Under mediation of the aza-crown ether-derived chiral BINOL and in the presence of a magnesium salt, an array of chiral γ,δ-unsaturated ketones were furnished in good enantioselectivities (81-95% ees).